The Collaborative International Dictionary of English v.0.48:

Tenure \Ten"ure\, n. [F. tenure, OF. teneure, fr. F. tenir to
   hold. See Tenable.]
   1. The act or right of holding, as property, especially real
      estate.
      [1913 Webster]

            That the tenure of estates might rest on equity, the
            Indian title to lands was in all cases to be
            quieted.                              --Bancroft.
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   2. (Eng. Law) The manner of holding lands and tenements of a
      superior.
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   Note: Tenure is inseparable from the idea of property in
         land, according to the theory of the English law; and
         this idea of tenure pervades, to a considerable extent,
         the law of real property in the United States, where
         the title to land is essentially allodial, and almost
         all lands are held in fee simple, not of a superior,
         but the whole right and title to the property being
         vested in the owner. Tenure, in general, then, is the
         particular manner of holding real estate, as by
         exclusive title or ownership, by fee simple, by fee
         tail, by courtesy, in dower, by copyhold, by lease, at
         will, etc.
         [1913 Webster]

   3. The consideration, condition, or service which the
      occupier of land gives to his lord or superior for the use
      of his land.
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   4. Manner of holding, in general; as, in absolute
      governments, men hold their rights by a precarious tenure.
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            All that seems thine own,
            Held by the tenure of his will alone. --Cowper.
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   Tenure by fee alms. (Law) See Frankalmoigne.
      [1913 Webster]

WordNet (r) 3.0 (2006):

tenure
    n 1: the term during which some position is held [syn: tenure,
         term of office, incumbency]
    2: the right to hold property; part of an ancient hierarchical
       system of holding lands [syn: tenure, land tenure]
    v 1: give life-time employment to; "She was tenured after she
         published her book"

Moby Thesaurus II by Grady Ward, 1.0:

103 Moby Thesaurus words for "tenure":
   adverse possession, alodium, appointment, berth, billet, burgage,
   claim, clamp, clasp, clench, clinch, clutch, colony,
   continuous tenure, de facto, de jure, dependency, derivative title,
   duration, employment, engagement, enlistment, fee fief,
   fee position, fee simple, fee simple absolute,
   fee simple conditional, fee simple defeasible,
   fee simple determinable, fee tail, feodum, feud, fiefdom,
   frankalmoign, free socage, freehold, gavelkind, gig, grapple,
   grasp, grip, gripe, having title to, hitch, hold, holding,
   incumbency, job, knight service, lay fee, lease, leasehold,
   legal claim, legal possession, mandate, moonlighting, occupancy,
   occupation, office, opening, original title, owning, permanence,
   permanency, place, position, possessing, possession, post,
   preoccupancy, preoccupation, prepossession, prescription,
   prison term, property, property rights, proprietary rights,
   residence, residency, second job, seisin, service, situation,
   socage, spell, squatting, station, stretch, sublease, tenancy,
   tenantry, tenure in chivalry, term, time, title, tour, underlease,
   undertenancy, usucapion, vacancy, villein socage, villeinhold,
   villenage



Bouvier's Law Dictionary, Revised 6th Ed (1856):

TENURE, estates. The manner in which lands or tenements are holden.
     2. According to the English law, all lands are held mediately or
immediately from the king, as lord paramount and supreme proprietor of all
the lands in the kingdom. Co. Litt. 1 b, 65 a; 2 Bl. Com. 105.
     3. The idea of tenure; pervades, to a considerable degree, the law of
real property in the several states; the title to land is essentially
allodial, and every tenant in fee simple has an absolute and perfect title,
yet in technical language, his estate is called an estate in fee simple, and
the tenure free and common socage. 3 Kent, Com. 289, 290. In the states
formed out of the North Western Territory, it seems that the doctrine of
tenures is not in force, and that real estate is owned by an absolute and
allodial title. This is owing to the wise provisions on this subject
contained in the celebrated ordinance of 1787. Am. Jur. No. 21, p. 94, 5. In
New York, 1 Rev. St. 718; Pennsylvania, 5 Rawle, R. 112; Connecticut, 1 Rev.
L. 348 and Michigan, Mich. L. 393, feudal tenures have been abolished, and
lands are held by allodial titles. South Carolina has adopted the statute,
12 C. II., c. 24, which established in England the tenure of free and common
socage. 1 Brev. Dig. 136. Vide Wright on Tenures; Bro. h.t.; Treatises of
Feuds and Tenures by Knight's service; 20 Vin Ab. 201; Com. Dig. h.t.; Bac.
Ab. h. Thom. Co. Litt. Index, h.t.; Sulliv. Lect. Index, h.t.